Venous valve apparatus, system, and method

ABSTRACT

A venous valve with a tubular frame that includes an outer surface and an inner surface opposite the outer surface and defining a lumen, and a cover over at least the outer surface of the tubular frame, where the cover includes surfaces defining a reversibly sealable opening for unidirectional flow of a liquid through the lumen. A system with the venous valve and a catheter including a proximal end and a distal end, the venous valve located between the proximal end and distal end of the catheter. A method including forming the venous valve and reversibly joining the venous valve and a catheter. A method including positioning at least part of the catheter including the venous valve at a predetermined location and deploying the venous valve from the catheter at the predetermined location.

FIELD OF THE INVENTION

The present invention relates generally to apparatus, systems, andmethods for use in a lumen; and more particularly to venous valveapparatus, systems, and methods for use in the vasculature system.

BACKGROUND OF THE INVENTION

The venous system of the legs uses pumps and valves to return blood tothe heart. Venous valves create one way flow to prevent blood fromflowing away from the heart. When valves fail, blood can pool in thelower legs resulting in swelling and ulcers of the leg. The absence offunctioning venous valves can lead to chronic venous insufficiency.

Techniques for both repairing and replacing the valves exist, but aretedious and require invasive surgical procedures. Direct and indirectvalvuoplasty procedures are used to repair damaged valves. Transpositionand transplantation are used to replace an incompetent valve.Transposition involves moving a vein with an incompetent valve to a sitewith a competent valve. Transplantation replaces an incompetent valvewith a harvested valve from another venous site. Prosthetic valves canbe transplanted into the venous system, but current devices are notsuccessful enough to see widespread usage.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B illustrate an embodiment of a valve.

FIGS. 2A-2D illustrate an embodiment of a valve in perspective view(FIGS. 2A and 2B) and sectional view (FIGS. 2C and 2D) of the valve.

FIGS. 3A and 3B illustrate an embodiment of a valve in a compressedstate (FIG. 3A) and in an expanded state (FIG. 3B).

FIGS. 4A-4D illustrate an embodiment of forming a valve.

FIGS. 5A-5C illustrate an embodiment of forming a cover.

FIGS. 6A-4E illustrate an embodiment of forming a valve.

FIGS. 7A-7D illustrate an embodiment of forming a valve.

FIG. 8 illustrates an embodiment of a system that includes a valve.

FIG. 9 illustrates an embodiment of a system that includes a valve.

FIG. 10 illustrates an embodiment of a system that includes a valve.

DETAILED DESCRIPTION

Embodiments of the present invention are directed to an apparatus,system, and method for valve replacement. For example, the apparatus caninclude a valve that can be used to replace an incompetent valve in abody lumen. Embodiments of the valve can include a tubular frame andcover that can be implanted through minimally-invasive techniques intothe body lumen. In one example, embodiments of the apparatus, system,and method for valve replacement may help to maintain antegrade bloodflow, while decreasing retrograde blood flow in a venous system ofindividuals having venous insufficiency, such as venous insufficiency inthe legs.

The Figures herein follow a numbering convention in which the firstdigit or digits correspond to the drawing Figure number and theremaining digits identify an element or component in the drawing.Similar elements or components between different Figures may beidentified by the use of similar digits. For example, 110 may referenceelement “10” in FIG. 1, and a similar element may be referenced as 210in FIG. 2. As will be appreciated, elements shown in the variousembodiments herein can be added, exchanged, and/or eliminated so as toprovide any number of additional embodiments of valve.

FIGS. 1A-3 provide illustrations of various embodiments of a valve ofthe present invention. Generally, valve can be implanted within thefluid passageway of a body lumen, such as for replacement of a valvestructure within the body lumen (e.g., a venous valve), to regulate theflow of a bodily fluid through the body lumen in a single direction.FIGS. 1A and 1B illustrate one embodiment of a venous valve 100. Venousvalve 100 includes a tubular frame 102 and a cover 104 for the venousvalve 100, where both the tubular frame 102 and the cover 104 canresiliently radially collapse and expand. The tubular frame 102 includesan outer surface 106 and an inner surface 108 opposite the outer surface106. The inner surface 108 defines a lumen 110 of the venous valve 100for passing fluid (e.g., blood) therethrough. The tubular frame 102 alsoincludes a first end 112 and a second end 114.

In one embodiment, the cover 104 can be located over at least the outersurface 106 of the tubular frame 102. For example, the cover 104 canextend around a perimeter of the tubular frame 102 so as to completelycover the outer surface of the tubular frame 102. In other words, thecover 104 extends over the outer surface of the tubular frame 102 sothat there are no exposed portions of the outer surface of the tubularframe 102. In an additional embodiment, the cover 104 can also belocated over at least the inner surface 108 of the tubular frame 102. Afurther embodiment includes the cover 104 located over at least theouter surface 106 and the inner surface 108. The cover 104 can furtherinclude surfaces defining a reversibly sealable opening 116 forunidirectional flow of a liquid through the lumen 110. For example, thesurfaces of the cover 104 can be deflectable between a closedconfiguration in which fluid flow through the lumen 110 can berestricted and an open configuration in which fluid flow through thelumen 110 can be permitted.

The tubular frame 102 can be formed from a wide variety of materials andin a wide variety of configurations. Generally, tubular frame 102 canhave a unitary structure with an open frame configuration. For example,the open frame configuration can include frame members 117 that defineopenings 119 through the tubular frame 102. The tubular frame 102 canalso be self-expanding. Examples of self-expanding frames include thoseformed from temperature-sensitive memory alloy which changes shape at adesignated temperature or temperature range. Alternatively, theself-expanding frames can include those having a spring-bias. Inaddition, the tubular frame 102 can have a configuration that allows theframe 102 be radially expandable through the use of a balloon catheter.

In one embodiment, the tubular frame 102 can include an open frameconfiguration that includes a first vertex 118 and a second vertex 120relative the first end 112 of the tubular frame 102. Tubular frame 102can further include a first valley 122 and a second valley 124 adjacentthe first end 112 relative the first vertex 118 and the second vertex120. As illustrated in FIGS. 1A and 1B, the first vertex 118 and thesecond vertex 120 can be positioned opposite each other along a commonaxis 126. FIGS. 1A and 1B also illustrate that the first valley 122 andthe second valley 124 can be positioned opposite each other andperpendicular to axis 126. Other relative positions for the first andsecond vertex 118 and 120, and the first and second valley 122 and 124are also possible.

FIGS. 2A-2D illustrate an additional embodiment of a venous valve 200.FIGS. 2A and 2B provide a perspective illustration of valve 200 in anopen configuration (FIG. 2A) and a closed configuration (FIG. 2B). FIGS.2C and 2D provide a sectional view of FIGS. 2A and 2B, respectively, tomore clearly illustrate the embodiment of the venous valve 200.

Venous valve 200 includes a tubular frame 202 and a cover 204 for thevenous valve 200 where both the tubular frame 202 and the cover 204 canresiliently radially collapse and expand. The tubular frame 202 includesan outer surface 206 and an inner surface 208 opposite the outer surface206. The inner surface 208 defines a lumen 210 of the venous valve 200for passing fluid (e.g., blood) therethrough. The tubular frame 202 alsoincludes a first end 212 and a second end 214.

In one embodiment, the cover 204 can be located over at least the outersurface 206 of the tubular frame 202. In an additional embodiment, thecover 204 can be located over at least the inner surface 208 of thetubular frame 202. A further embodiment includes the cover 204 locatedover at least the outer surface 206 and the inner surface 208. The cover204 further includes surfaces defining a reversibly sealable opening 216for unidirectional flow of a liquid through the lumen 210. For example,the surfaces of the cover 204 can be deflectable between a closedconfiguration in which fluid flow through the lumen 210 can berestricted and an open configuration in which fluid flow through thelumen 210 can be permitted.

Generally, tubular frame 202 can have a unitary structure with an openframe configuration. For example, the open frame configuration caninclude frame members 217 that define openings 219 through the tubularframe 202. The tubular frame 202 can include an open frame configurationin which the first end 212 and the second end 214 each include aplurality of end portions 221 that lay on a common plane 223. Asillustrated in FIGS. 2A-2D, the plurality of end portions 221 that layon the common plane 223. However, the plurality of end portions 221 neednot all lay on the common plane 223 and 222. It is possible that one ormore of the end portions 221 lay above and/or below the common plane223.

While the tubular frame 102 and/or 202 illustrated herein is shownhaving a circular configuration, other configurations are also possible.For example, the tubular frame 102 and/or 202 can also include anelliptical configuration. As such, the present invention should not belimited to the illustration of the tubular frame 102 and/or 202.

The tubular frame 202 further includes elastic regions 228. Typically,the elastic regions 228 can occur at portions of the tubular frame 202that include curves 230 in the frame members 217. The elastic regions228 allow the valve 200 to accommodate changes in body lumen size (e.g.,diameter of the body lumen) by flexing to expand and/or contract tochange the diameter of the tubular frame 202. In one embodiment, thecurves 230 in the frame members 217 can act as springs to allow thevalve 200 to resiliently radially collapse and expand. The valve frame202 can also provide sufficient contact and expansion force with thesurface of a body lumen wall to encourage fixation of the valve 200 andto prevent retrograde flow within the body lumen. Anchoring elements(e.g., barbs) can also be included with valve 200, as will be discussedherein.

The elastic regions 228 of the valve frame 202 allow valve 200 toelastically and repeatably travel between a collapsed state and anexpanded state. FIG. 3A provides an example of the valve 300 in acollapsed state, and FIG. 3B provides an example of the valve 300 in anexpanded state. As shown in FIGS. 3A and 3B, the valve 300 can travelbetween the collapsed and the expanded state along a radial travel path336, where there can be a change in a cross sectional area 338 of thelumen 310. For example, the valve frame 302 can travel along the radialtravel path 336 so as to change a width 340 of lumen 310. This can allowthe valve 300 to react appropriately to any distension and contractionof the lumen in which the valve 300 is placed.

In addition to the curves 230, the elastic regions 228 can furtherinclude, but are not limited to, other shapes for the valve frame 202that allow for repeatable travel between the collapsed state and theexpanded state. For example, the elastic regions 228 can includeintegrated springs having a circular or an elliptical coilconfiguration. Other shapes are also possible.

Frame member 217 of the valve frame 202 can include a variety ofcross-sectional shapes and dimensions. For example, cross-sectionalshapes for the frame member 217 can include, but are not limited to,circular, tubular, I-shaped, T-shaped, oval, trapezoidal, andtriangular. The frame member 217 can also have a single cross-sectionalshape (e.g., all of valve frame 202 can have a circular cross-sectionalshape). In an additional embodiment, the frame member 217 can have twoor more cross-sectional shapes (e.g., a circular cross-sectional shapein the elastic region 228 and a different cross-sectional shape in otherregions of valve frame 202).

Valve frame 202 can also include one or more contiguous frame member217. For example, the frame member 217 of valve frame 202 can be asingle contiguous member. The single contiguous member can be bentaround an elongate tubular mandrel to form the valve frame 202. The freeends of the single contiguous member can then be welded, fused, crimped,or otherwise joined together to form the valve frame 202. In anadditional embodiment, the frame member 217 of valve frame 202 can bederived (e.g., laser cut, water cut) from a single tubular segment. Inan alternative embodiment, methods of joining the frame member 217 tocreate the elastic region 228 include, but are not limited to, welding,gluing, and fusing the frame member 217. The valve frame 202 can be heatset by a method as is typically known for the material which forms thevalve frame 202.

The valve frame 202 can be formed from any number of materials. Forexample, the valve frame 202 can be formed from a biocompatible metal,metal alloy, polymeric material, or combination thereof. As discussedherein, the valve frame 202 can be self-expanding or balloon expandable.In addition, the valve frame 202 can be configured so as to have theability to move radially between the collapsed state and the expandedstate. To accomplish this, the material used to form the valve frame 202should exhibit a low elastic modulus and a high yield stress for largeelastic strains that can recover from elastic deformations. Examples ofsuitable materials include, but are not limited to, medical gradestainless steel (e.g., 316L), titanium, tantalum, platinum alloys,niobium alloys, cobalt alloys, alginate, or combinations thereof. In anadditional embodiment, the valve frame 202 may be formed from ashape-memory material, such as shape memory plastics, polymers, andthermoplastic materials which are inert in the body. Shaped memoryalloys having superelastic properties generally made from specificratios of nickel and titanium, commonly known as nitinol, are alsopossible materials. Other materials are also possible.

Tubular frame 202 can be expanded to provide lumen 210 having any numberof sizes. For example, the size of lumen 210 can be determined basedupon the type of body lumen and the body lumen size in which the valve200 is to be placed. In an additional example, there can also be aminimum value for the width 240 for the tubular frame 202 that ensuresthat the tubular frame 202 will have an appropriate expansion forceagainst the inner wall of the body lumen in which the valve 200 is beingplaced. The tubular frame 202 can also include a longitudinal length242.

In one embodiment, the valve frame 202 can further include one or moreanchoring elements. For example, the one or more anchoring elements caninclude, but are not limited to, one or more barbs 243 projecting fromthe outer surface 206 of the tubular frame 202. The valve 200 canfurther include one or more radiopaque markers (e.g., tabs, sleeves,welds). For example, one or more portions of the valve frame 202 can beformed from a radiopaque material. Radiopaque markers can be attached toand/or coated onto one or more locations along the valve frame 202.Examples of radiopaque material include, but are not limited to, gold,tantalum, and platinum. The position of the one or more radiopaquemarkers can be selected so as to provide information on the position,location and orientation of the valve 200 during its implantation.

As discussed herein, valve 100 further includes cover 104 havingsurfaces defining the reversibly sealable opening 116 for unidirectionalflow of a liquid through the lumen 110. For the embodiment illustratedin FIGS. 1A and 1B, the cover 104 extends over at least a portion of thetubular frame 102 to a first connection point 144 and a secondconnection point 146 on the tubular frame 102. In one example, the firstconnection point 144 and the second connection point 146 can be locatedat the first vertex 118 and the second vertex 120 of the tubular frame102. The cover 104 extends between the first connection point 144 andthe second connection point 146 to provide a first valve leaflet 132 anda second valve leaflet 134. The first valve leaflet 132 and the secondvalve leaflet 134 can form the reversibly sealable opening 116 extendingbetween the first connection point 144 and the second connection point146. So, for the example shown in FIG. 1 the first valve leaflet 132 andthe second valve leaflet 134 form the reversibly sealable opening 116extending between the first vertex 118 and the second vertex 120 of thetubular frame 102.

As illustrated, the first valve leaflet 132 and the second valve leaflet134 include a region 148 of the cover 104 that can move relative thetubular frame 102. The region 148 of the cover 104 can be unbound (i.e.,unsupported) by the tubular frame 102 and extends between the firstconnection point 144 and the second connection point 146 of the valve100. This configuration permits the reversibly sealable opening 116 toopen and close in response to the fluid pressure differential across thevalve leaflets 132 and 134.

For example, under antegrade fluid flow (i.e., positive fluid pressure)from the first end 112 towards the second end 114 of the valve 100, thefirst and second valve leaflets 132 and 134 can expand toward the innersurface 108 to create an opening through which fluid is permitted tomove. In one example, the first valve leaflet 132 and the second valveleaflet 134 can each expand to define a semi-tubular structure whenfluid opens the reversibly sealable opening 116. An example of the openconfiguration for the valve is shown in FIGS. 1A and 2A.

Under a retrograde fluid flow (i.e., negative fluid pressure) from thesecond end 114 towards the first end 112, the first and second valveleaflets 132 and 134 can move away from the inner surface 108 as thevalve leaflets 132 and 134 begin to close valve 100. In one example, apocket exists between the frame 102 and each of the first and secondvalve leaflets 132 and 134. The pocket allows fluid from the retrogradeflow to develop pressure on a first major face 150 of the first andsecond valve leaflets 132 and 134. As fluid pressure develops, the firstand second valve leaflets 132 and 134 collapse, closing the reversiblysealable opening 116 to create a seal 154, thereby restrictingretrograde fluid flow through the valve 100. In one example, the seal154 can be created by the joining of a sealing surface 156 of the firstand second valve leaflets 132 and 134. In the closed configuration, thefirst and second valve leaflets 132 and 134 can each have a concavestructure 158 when fluid closes the reversibly sealable opening 116. Anexample of the closed configuration for the valve is shown in FIGS. 1Band 2B.

Valve 100 provides an embodiment in which the surfaces defining thereversibly sealable opening 116 provide a bi-leaflet configuration(i.e., a bicuspid valve) for valve 100. Although the embodiments inFIGS. 1A-B and 2A-D illustrate and describe a bi-leaflet configurationfor the valve of the present invention, designs employing a differentnumber of valve leaflets (e.g., tri-leaflet valve) are possible. Forexample, additional connection points (e.g., three or more) could beused to provide additional valve leaflets (e.g., a tri-leaflet valve).

The first valve leaflet 132 and the second valve leaflet 134 can have avariety of sizes and shapes. For example, each of the first valveleaflet 132 and the second valve leaflet 134 can have a similar size andshape. In addition, each of the first valve leaflet 132 and the secondvalve leaflet 134 can include opposed first and second major surfaces150 and 152, respectively. Each first major surface 150 of the firstvalve leaflet 132 and the second valve leaflet 134 can be oriented toface the second end 114 of valve 100.

Each of the first valve leaflet 132 and the second valve leaflet 134 canfurther provide the sealing surface 156 formed by portions of the firstvalve leaflet 132 and the second valve leaflet 134, where the sealingsurface 156 can engage to define the closed configuration (FIG. 1B) ofvalve 100. Sealing surface 156 of the first valve leaflet 132 and thesecond valve leaflet 134 can separate to provide for an openconfiguration (FIG. 1A) of valve 100. In an additional example, each ofthe first valve leaflet 132 and the second valve leaflet 134 need nothave a similar size and shape (i.e., the valve leaflets can have adifferent size and shape with respect to each other).

In one embodiment, each of the first valve leaflet 132 and the secondvalve leaflet 134 includes sufficient excess material spanning tubularframe 102 such that fluid pressure (e.g., antegrade flow) acting on thesecond major surface 152 of the first valve leaflet 132 and the secondvalve leaflet 134 forces the valve 100 into an open configuration (FIG.1A). The first valve leaflet 132 and the second valve leaflet 134further include arcuate edges 160 and 162 that are positioned adjacenteach other along a substantially catenary curve between the connectionpoint 144 and the second connection point 146 in the closedconfiguration (FIG. 1B) of valve 100. Similarly, arcuate edges 160 and162 can define opening 116 when the valve 100 is in the openconfiguration (FIG. 1A).

In an additional embodiment, in the open configuration the portion ofthe cover 104 forming the first valve leaflet 132 and the second valveleaflet 134 provides sufficient excess material spanning between theconnection point 144 and the second connection point 146 to allow thefirst and second major surfaces 150 and 152 to take on a semi-tubularstructure 164, as shown in FIG. 1A, when fluid pressure opens the valve100. In an additional embodiment, arcuate edge 160 and 162 of valve 100can open to approximately the full inner diameter of a body lumen.

Each of the second major surfaces 152 of the first valve leaflet 132 andthe second valve leaflet 134 can further include a curve impartedthereto so as to provide the second major surface 152 with the concavestructure 158. The concave structure 158 allows the first valve leaflet132 and the second valve leaflet 134 to better collect retrograde fluidflow to urge the first valve leaflet 132 and the second valve leaflet134 towards the closed configuration. For example, as retrograde flowbegins, the first valve leaflet 132 and the second valve leaflet 134respond by moving towards the center of valve 100. As the first valveleaflet 132 and the second valve leaflet 134 approach the center of thedevice the sealing surfaces 156 make sufficient contact to effectivelyclose valve 100 and restrict retrograde fluid flow.

In an additional embodiment, the first valve leaflet 132 and the secondvalve leaflet 134 can include one or more support structures, where thesupport structures can be integrated into and/or onto the valve leaflets132 and 134. For example, the first valve leaflet 132 and the secondvalve leaflet 134 can include one or more support ribs having apredetermined shape. In one embodiment, the predetermined shape of thesupport ribs can include a curved bias so as to provide the first valveleaflet 132 and the second valve leaflet 134 with a curvedconfiguration. Support ribs can be constructed of a flexible materialand have dimensions (e.g., thickness, width and length) andcross-sectional shape that allows the support ribs to be flexible whenthe first valve leaflet 132 and the second valve leaflet 134 are urgedinto an open position, and stiff when the first valve leaflet 132 andthe second valve leaflet 134 are urged into a closed position uponexperiencing sufficient back flow pressure from the direction downstreamfrom the valve. In an additional embodiment, support ribs can also beattached to valve frame 102 so as to impart a spring bias to the valveleaflets in either the open or the closed configuration.

In one embodiment, the material of the first valve leaflet 132 and thesecond valve leaflet 134 can be sufficiently thin and pliable so as topermit radially-collapsing of the valve leaflets for delivery bycatheter to a location within a body lumen. The first valve leaflet 132and the second valve leaflet 134 can be constructed of afluid-impermeable biocompatible material that can be either synthetic orbiologic. Possible synthetic materials include, but are not limited to,expanded polytetrafluoroethylene (ePTFE), polytetrafluoroethylene(PTFE), polystyrene-polyisobutylene-polystyrene (SIBS), polyurethane,segmented poly(carbonate-urethane), Dacron, polyethylene (PE),polyethylene terephthalate (PET), silk, urethane, Rayon, Silicone, orthe like. Possible biologic materials include, but are not limited to,autologous, allogeneic or xenograft material. These include explantedveins and decellularized basement membrane materials, such as smallintestine submucosa (SIS) or umbilical vein.

As discussed herein, the cover 104 can be located over at least theouter surface 106 of the tubular frame 102. FIGS. 1A and 1B illustratethis embodiment. In an additional embodiment, the cover 104 can also belocated over at least the inner surface 108 of the tubular frame 102.FIGS. 2A-2D illustrate of this embodiment. In one example, the cover 104can further be located over the openings 119 defined by the members 117of the tubular frame 102. The cover 104 can also be joined to itselfthrough the openings 119 so as to fully or partially encase the tubularframe 102. Numerous techniques may be employed to laminate or bond cover104 on the outer surface 106 and/or the inner surface 108 of the tubularframe 102, including heat setting, adhesive welding, application ofuniform force and other bonding techniques. Additionally, the cover 104may be folded over the first end of the tubular frame 102 to provide thecover 104 on both the outer surface 106 and the inner surface 108. Cover104 can also be joined to itself and/or the members 117 according to themethods described in U.S. Patent Application Publication US 2002/0178570to Sogard et al., which is hereby incorporated by reference in itsentirety.

The cover 104 can also be coupled to the connection points so as to formthe valve leaflets, as discussed herein. In one embodiment, the cover104 can be in the form of a sheet or a sleeve of material, as discussedherein, which can be connected to the tubular frame 102. Alternatively,the cover 104 can initially be in the form of a liquid that can be usedto cast and/or form the cover over the tubular frame 102. Other forms,including intermediate forms, of the cover 104 are also possible.

The cover 104 can be coupled to the tubular frame 102, including theconnection points 144 and 146, in a variety of ways so as to provide thevarious embodiments of the valve of the present invention. For example,a variety of fasteners can be used to couple the cover 104 to thetubular frame 102 so as to form the valve 100. Suitable fasteners caninclude, but are not limited to, biocompatible staples, glues, suturesor combinations thereof. In an additional embodiment, the cover 104 canbe coupled to the tubular frame 102 through the use of heat sealing,solvent bonding, adhesive bonding, or welding cover 104 to either aportion of the cover 104 (i.e., itself) and/or the tubular frame 102.

The cover 104, including the valve leaflets 132 and 134, may also betreated and/or coated with any number of surface or material treatments.For example, the cover 104 can be treated with one or more biologicallyactive compounds and/or materials that may promote and/or inhibitendothelization and/or smooth muscle cell growth of the cover 104,including the valve leaflets 132 and 134. Similarly, the cover 104 maybe seeded and covered with cultured tissue cells (e.g., endothelialcells) derived from a either a donor or the host patient which areattached to the valve leaflets 132 and 134. The cultured tissue cellsmay be initially positioned to extend either partially or fully over thevalve leaflets 132 and 134.

Cover 104, in addition to forming valve leaflets 132 and 134, can alsobe capable of inhibiting thrombus formation. Additionally, cover 104 mayeither prevent or facilitate tissue ingrowth therethrough, as theparticular application for the valve 100 may dictate. For example, cover104 on the outer surface 106 may be formed from a porous material tofacilitate tissue ingrowth therethrough, while cover 104 on the innersurface 108 may be formed from a material or a treated material whichinhibits tissue ingrowth.

The embodiments of the valve of the present invention can be formed inany number of ways. For example, FIGS. 4A-4D provide an illustration ofa method for forming valve 400. FIG. 4A illustrates one embodiment ofcover 404 having a tubular configuration that includes a symmetricalportion 466 and a tapering portion 468. In the present example, thecover 404 can be formed from a continuous piece of tubular material. Inone example, the tapering portion 468 can be formed by removingpredetermined portions of the tubular material from the continuous pieceof tubular material.

For example, FIGS. 5A-5C illustrate one embodiment of creating atapering portion 568 for the cover 504. Cover 504 is shown in aflattened configuration to better illustrate forming the taperingportion 568 according to the present embodiment. As FIG. 5A illustrates,cover 504 can have an initial symmetrical configuration. FIG. 5A alsoillustrates that a portion 569, defined by line 570, of the cover 504 inthe symmetrical configuration for removal in forming the taperingportion. FIG. 5B shows the portion 569 removed from the cover 504. Onceremoved, the cover 504 includes edges 571 that are joined to form thetapering portion 568. FIG. 5C provides an example of edges 571 joinedfor the tapering portion 568. In one example, the edges 571 can bejoined in any number of ways, including any of those recited herein.

Other ways of forming the tapering portion 468 during the manufacturingof the cover 404 also exist. For example, the cover 404 can be cast,extruded, or molded (including blow molded) to form the tapering portion468. In addition, tapering portion 468 can be provided separately fromthe symmetrical portion 466. In other words, each portion (e.g.,tapering portion 468 and the symmetrical portion 466) are separatepieces that can either be then be joined, by method described herein, orused separately in forming valve 400.

In an alternative embodiment, the tapering portion 468 can be created asa result of at least a portion of the cover 404 being stretched over thetubular frame 402. For example, the cover 404 can have a cylindricalshape of essentially uniform inner diameter, where the inner diameter isless than an outer diameter of the tubular frame 402. The cover 404 canbe stretched over the outer surface 406 of the tubular frame 402 suchthat the tapering portion 468 results as the cover 404 transitions fromits stretched portion over the tubular frame 402 to the unstretchedportion of the cover 404.

Referring again to FIGS. 4B-4D, the symmetrical portion 466 of the cover404 can be placed around the outer surface 406 of the tubular frame 402.For example, the cover 404 can stretched slightly to allow the tubularframe 402 to be placed within the symmetrical portion 466 of the cover404. Alternatively, the outer diameter of the tubular frame 402 could beenlarged so as to place the symmetrical portion 466 of the cover 404around the outer surface 406 of the tubular frame 402. Other ways ofplacing the symmetrical portion 466 of the cover 404 around the outersurface 406 of the tubular frame 402 are also possible.

As FIG. 4C illustrates, a free end 472 of the tapering portion 468 canbe folded and drawn into the lumen 410 of the tubular frame 402. Thefree end 472 is advanced toward the second end 414, so that the cover404 extends over at least a portion of the inner surface 408 of thetubular frame 402. The free end 472 of the cover 404 can extend over atleast the portion of the inner surface 408 to at least a firstconnection point 444 and a second connection point 446 on the tubularframe 402. As FIG. 4D illustrates, the cover 404 can be attached at thefirst connection point 444 and the second connection point 446 to formthe first valve leaflet 432 and the second valve leaflet 434. Asdiscussed herein, the first valve leaflet 432 and the second valveleaflet 434 include sealing surfaces 456 defining the reversiblysealable opening 416 for unidirectional flow of liquid through the lumen410.

FIG. 4D further illustrates the cover 404 located over the outer surface406 may be affixed to the cover 404 over at least a portion of the innersurface 408 through the openings 419 and/or affixed to the members 417of the tubular frame 402. In addition, the cover 404 located over theouter surface 406 may be affixed at least to the members 417 of thetubular frame 402.

FIG. 6A-6E provides an alternative embodiment of forming a valve 600. Inthe present embodiment, the cover 604 can include at least two separateportions (e.g., symmetrical portion 666 shown in FIG. 6A and taperingportion 668 shown in FIG. 6B) that are affixed to the tubular frame 602to form the valve 600. For example, the cover 604 can be formed from asymmetrical portion 666, shown in FIG. 6A, that is separate from atapering portion 668, shown in FIG. 6B.

The tapering portion 668 and the symmetrical portion 666 can be affixedto the tubular frame 602 and to each other, as described herein, so asto form valve 600. For example, FIGS. 6C-6D illustrate symmetricalportion 666 affixed to tubular frame 602, with tapering portion 668being inserted into lumen 610. FIG. 6E illustrates valve 600 uponaffixing the tapering portion 668 to the symmetrical portion 666, thetubular frame 602 and the first and second connection points 644 and646.

FIGS. 7A-7D illustrate an additional embodiment of forming a valve 700according to the present invention. The valve 700 includes tubular frame702 (FIG. 7A) and cover 704 (FIG. 7B). As discussed herein, tubularframe 702 has an open frame configuration that includes the first vertex718 and a second vertex 720 relative the first end 712 of the tubularframe 702. In the present example, the cover 704 can have a tubularconfiguration, where the cover 704 can be positioned around and affixedto the tubular frame 702 (FIGS. 7C-7D) so as to form valve 700. Forexample, cover 704 and/or tubular frame 702 can be stretched so as toaffix the cover 704 and the tubular frame 702. In addition, the cover704 can be affixed to the tubular frame 702 by additional mechanicaland/or chemical approaches, as discussed herein.

FIG. 8 illustrates one embodiment of a system 882. System 882 includesvalve 800, as described herein, reversibly joined to catheter 874. Thecatheter 874 includes an elongate body 876 having a proximal end 878 anda distal end 879, where valve 800 can be located between the proximalend 878 and distal end 879. The catheter 874 can further include a lumen880 longitudinally extending to the distal end 879. In one embodiment,lumen 880 extends between proximal end 878 and distal end 879 ofcatheter 874. The catheter 874 can further include a guidewire lumen 881that extends within the elongate body 876, where the guidewire lumen 881can receive a guidewire for positioning the catheter 874 and the valve800 within a body lumen (e.g., a vein of a patient).

The system 882 can further include a deployment shaft 883 positionedwithin lumen 880, and a sheath 884 positioned adjacent the distal end879. In one embodiment, the valve 800 can be positioned at leastpartially within the sheath 884 and adjacent the deployment shaft 883.The deployment shaft 883 can be moved within the lumen 880 to deployvalve 800. For example, deployment shaft 883 can be used to push valve800 from sheath 884 in deploying valve 800.

FIG. 9 illustrates an additional embodiment of the system 982. Thecatheter 974 includes elongate body 976, lumen 980, a retraction system986 and a retractable sheath 987. The retractable sheath 987 can bepositioned over at least a portion of the elongate body 976, where theretractable sheath 987 can move longitudinally along the elongate body976. The valve 900 can be positioned at least partially within theretractable sheath 987, where the retractable sheath 987 moves along theelongate body 976 to deploy the valve 900. In one embodiment, retractionsystem 986 includes one or more wires coupled to the retractable sheath987, where the wires are positioned at least partially within and extendthrough lumen 980 in the elongate body 976. Wires of the retractionsystem 986 can then be used to retract the retractable sheath 987 indeploying valve 900.

FIG. 10 illustrates an additional embodiment of the system 1082. Thecatheter 1074 includes elongate body 1076, an inflatable balloon 1088positioned adjacent the distal end 1079, and a lumen 1080 longitudinallyextending in the elongate body 1076 of the catheter 1074 from theinflatable balloon 1088 to the proximal end 1078. In the presentexample, the inflatable balloon 1088 can be at least partiallypositioned within the lumen 1010 of the valve 1000. The inflatableballoon 1088 can be inflated through the lumen 1080 to deploy the valve1000.

The embodiments of the present invention further include methods forforming the valve of the present invention, as discussed herein. Forexample, the valve can be formed from the tubular frame and the coverover at least the outer surface of the tubular frame, where the coverincludes surfaces defining the reversibly sealable opening forunidirectional flow of a liquid through the lumen. In an additionalexample, the valve can be reversibly joined to the catheter, which caninclude a process of altering the shape of the valve from a first shape,for example an expanded state, to the compressed state, as describedherein.

For example, the valve can be reversibly joined with the catheter bypositioning valve in the compressed state at least partially within thesheath of the catheter. In one embodiment, positioning the valve atleast partially within the sheath of the catheter includes positioningthe valve in the compressed state adjacent the deployment shaft of thecatheter. In an another embodiment, the sheath of the catheter functionsas a retractable sheath, where the valve in the compressed state can bereversibly joined with the catheter by positioning the valve at leastpartially within the reversible sheath of the catheter. In a furtherembodiment, the catheter can include an inflatable balloon, where theballoon can be positioned at least partially within the lumen of thevalve, for example, in its compressed state.

The embodiments of the valve described herein may be used to replace,supplement, or augment valve structures within one or more lumens of thebody. For example, embodiments of the present invention may be used toreplace an incompetent venous valve and help to decrease backflow ofblood in the venous system of the legs.

In one embodiment, the method of replacing, supplementing, and/oraugmenting a valve structure can include positioning at least part ofthe catheter including the valve at a predetermined location within thelumen of a body. For example, the predetermined location can include aposition within a body lumen of a venous system of a patient, such as avein of a leg.

In one embodiment, positioning the catheter that includes the valvewithin the body lumen of a venous system includes introducing thecatheter into the venous system of the patient using minimally invasivepercutaneous, transluminal catheter based delivery system, as is knownin the art. For example, a guidewire can be positioned within a bodylumen of a patient that includes the predetermined location. Thecatheter, including valve, as described herein, can be positioned overthe guidewire and the catheter advanced so as to position the valve ator adjacent the predetermined location. In one embodiment, radiopaquemarkers on the catheter and/or the valve, as described herein, can beused to help locate and position the valve.

The valve can be deployed from the catheter at the predeterminedlocation in any number of ways, as described herein. In one embodiment,valve of the present invention can be deployed and placed in any numberof vascular locations. For example, valve can be deployed and placedwithin a major vein of a patient's leg. In one embodiment, major veinsinclude, but are not limited to, those of the peripheral venous system.Examples of veins in the peripheral venous system include, but are notlimited to, the superficial veins such as the short saphenous vein andthe greater saphenous vein, and the veins of the deep venous system,such as the popliteal vein and the femoral vein.

As discussed herein, the valve can be deployed from the catheter in anynumber of ways. For example, the catheter can include the retractablesheath in which valve can be at least partially housed, as discussedherein. Valve can be deployed by retracting the retractable sheath ofthe catheter, where the valve self-expands to be positioned at thepredetermined location. In an additional example, the catheter caninclude a deployment shaft and sheath in which valve can be at leastpartially housed adjacent the deployment shaft, as discussed herein.Valve can be deployed by moving the deployment shaft through thecatheter to deploy valve from the sheath, where the valve self-expandsto be positioned at the predetermined location. In an additionalembodiment, the valve can be deployed through the use of an inflatableballoon.

Once implanted, the valve can provide sufficient contact and expansionforce against the body lumen wall to prevent retrograde flow between thevalve and the body lumen wall. For example, the valve can be selected tohave a larger expansion diameter than the diameter of the inner wall ofthe body lumen. This can then allow valve to exert a force on the bodylumen wall and accommodate changes in the body lumen diameter, whilemaintaining the proper placement of valve. As described herein, thevalve can engage the lumen so as to reduce the volume of retrograde flowthrough and around valve. It is, however, understood that some leakingor fluid flow may occur between the valve and the body lumen and/orthrough valve leaflets.

While the present invention has been shown and described in detailabove, it will be clear to the person skilled in the art that changesand modifications may be made without departing from the spirit andscope of the invention. As such, that which is set forth in theforegoing description and accompanying drawings is offered by way ofillustration only and not as a limitation. The actual scope of theinvention is intended to be defined by the following claims, along withthe full range of equivalents to which such claims are entitled.

In addition, one of ordinary skill in the art will appreciate uponreading and understanding this disclosure that other variations for theinvention described herein can be included within the scope of thepresent invention. For example, the tubular frame 102 and/or the cover104 can be coated with a non-thrombogenic biocompatible material, as areknown or will be known.

In the foregoing Detailed Description, various features are groupedtogether in several embodiments for the purpose of streamlining thedisclosure. This method of disclosure is not to be interpreted asreflecting an intention that the embodiments of the invention requiremore features than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter lies in less than allfeatures of a single disclosed embodiment. Thus, the following claimsare hereby incorporated into the Detailed Description, with each claimstanding on its own as a separate embodiment.

What is claimed is:
 1. A venous valve, comprising: a radiallycollapsible and expandable tubular frame with an open frameconfiguration, wherein the tubular frame includes an outer surface andan inner surface opposite the outer surface and defining a lumen, onlyone band of wishbone-shaped frame members, the band of wishbone-shapedframe members formed about a first end of the frame, and a first vertexand a second vertex relative the first end of the tubular frame, a firstvalley and a second valley extending from the first vertex and thesecond vertex to the first end of the tubular frame, wherein the firstvertex and the second vertex are positioned opposite one another along acommon axis, and wherein the first valley and the second valley arepositioned opposite one another and are perpendicular to the commonaxis, and wherein, a first strut of the tubular frame passes immediatelyfrom the first vertex to the first valley and a second strut of thetubular frame passes immediately from the first valley to the secondvertex to form a tapering point, and wherein each of the first strut andthe second strut comprise a half-wishbone shape; and a radiallycollapsible and expandable tubular cover positioned around the entireouter surface of the tubular frame, wherein the tubular cover isconnected to the first vertex and to the second vertex to form a firstvalve leaflet across the first valley and a second valve leaflet acrossthe second valley between the first vertex and the second vertex tooppose flow of a liquid through the lumen from the second end to thefirst end.
 2. The venous valve of claim 1, wherein the first valveleaflet and the second valve leaflet include arcuate edges at one end ofthe tubular cover to define a reversibly sealable opening extendingbetween the first vertex and the second vertex.
 3. The venous valve ofclaim 1, further including the cover over the inner surface of thetubular frame, wherein the cover over the inner surface extends to atleast a first connection point and a second connection point on thetubular frame to form a first valve leaflet and a second valve leaflet.4. The venous valve of claim 3, wherein the first valve leaflet and thesecond valve leaflet form the reversibly sealable opening extendingbetween the first connection point and the second connection point.
 5. Avenous valve, comprising: a radially collapsible and expandable tubularframe with an open frame configuration including only one band ofwishbone-shaped frame members, the band of wishbone-shaped frame membersformed about a first end of the frame, a first vertex and a secondvertex relative the first end of the tubular frame, wherein the firstvertex and the second vertex are positioned opposite each other along acommon axis, a first valley and a second valley extending from the firstvertex and the second vertex to the first end of the tubular frame, andwherein the first valley and the second valley are positioned oppositeeach other and are perpendicular to the common axis, and wherein thetubular frame includes an outer surface and an inner surface oppositethe outer surface and defining a lumen, and a first strut of the tubularframe passes immediately from the first vertex to the first valley and asecond strut of the tubular frame passes immediately from the firstvalley to the second vertex to form a tapering point, and wherein eachof the first strut and the second strut comprise a half-wishbone shape;and a radially collapsible and expandable tubular cover extending overthe entire outer surface of the tubular frame and connected to the firstvertex and the second vertex to form a first valve leaflet and a secondvalve leaflet therebetween, wherein the first valve leaflet and thesecond valve leaflet reversibly transition between an open position anda closed position opposing flow of a liquid in one direction through thelumen.
 6. The venous valve of claim 5, wherein the first valve leafletand the second valve leaflet form a reversibly sealable openingextending between the first vertex and the second vertex.
 7. The venousvalve of claim 5, wherein the tubular frame and the tubular cover movebetween a collapsed state and an expanded state.
 8. The venous valve ofclaim 5, wherein the first valve leaflet and the second valve leafletinclude arcuate edges between the first vertex and the second vertex. 9.A system, comprising: a venous valve, wherein the venous valve includes:a radially collapsible and expandable tubular frame with an open frameconfiguration, wherein the tubular frame includes an outer surface andan inner surface opposite the outer surface and defining a lumen, onlyone band of wishbone-shaped frame members, the band of wishbone-shapedframe members formed about a first end of the frame, the frame having afirst vertex and a second vertex relative the first end of the tubularframe, wherein the first vertex and the second vertex are positionedopposite each other along a common axis, and having a first valley and asecond valley extending from the first vertex and the second vertex tothe first end of the tubular frame, wherein the first valley and thesecond valley are positioned opposite each other and are perpendicularto the common axis and a first strut of the tubular frame passesimmediately from the first vertex to the first valley and a second strutof the tubular frame passes immediately from the first valley to thesecond vertex to form a tapering point, and wherein each of the firststrut and the second strut comprise a half-wishbone shape; a radiallycollapsible and expandable tubular cover that extends over at least theentire outer surface of the tubular frame and is connected to the firstvertex and the second vertex on the tubular frame to form a first valveleaflet and a second valve leaflet between the first vertex and thesecond vertex, where the first valve leaflet and the second valveleaflet reversibly transition between an open position and a closedposition opposing flow of a liquid from the first end through the lumen;and a catheter including a proximal end and a distal end, the venousvalve located between the proximal end and distal end of the catheter.10. The system of claim 9, wherein the catheter includes an elongatebody having a lumen longitudinally extending to the distal end, adeployment shaft positioned within the lumen, and a sheath positionedadjacent the distal end, the venous valve positioned at least partiallywithin the sheath and adjacent the deployment shaft, wherein thedeployment shaft moves within the lumen to deploy the venous valve. 11.The system of claim 9, wherein the catheter includes an elongate bodyand a retractable sheath over at least a portion of the elongate body,the venous valve positioned at least partially within the retractablesheath, wherein the retractable sheath moves along the elongate body todeploy the venous valve.
 12. The system of claim 9, wherein the catheterincludes an inflatable balloon positioned adjacent the distal end and acatheter lumen longitudinally extending in an elongate body of thecatheter from the inflatable balloon to the distal end, the inflatableballoon at least partially positioned within the lumen of the venousvalve, where the inflatable balloon inflates to deploy the venous valve.13. The system of claim 9, wherein the tubular cover extends to at leastthe first vertex and the second vertex to form a first valve leaflet anda second valve leaflet between the first vertex and the second vertex,wherein the first valve leaflet and the second valve leaflet includes asurface defining a reversibly sealable opening for unidirectional flowof a liquid through the lumen.
 14. The system of claim 9, wherein thecover extends over at least a portion of the inner surface of thetubular frame, wherein the cover over the at least the portion of theinner surface extends to at least a first connection point and a secondconnection point on the tubular frame to form a first valve leaflet anda second valve leaflet, wherein the first valve leaflet and the secondvalve leaflet includes a surface defining a reversibly sealable openingfor unidirectional flow of a liquid through the lumen.